[PATCH v5 07/13] ARM: dts: imx6ul: Add Variscite WM8904 and WM8731 support

From: Stefano Radaelli

Date: Thu Oct 08 2026 - 15:41:41 EST

From: Stefano Radaelli <stefano.r@xxxxxxxxxxxxx>

Add shared WM8904 and WM8731 codec and sound-card descriptions for
VAR-SOM-6UL and DART-6UL. Reuse imx6ul-var-som-audio.dtsi for SAI2
and select the clock setup and audio routes in each codec file.
The DART-6UL WM8904 wrapper adds the IN2L, IN2R and MICBIAS routes.

The existing Concerto DTS files enable SAI2 but do not describe a
codec or sound card. Include the WM8904 option there to connect the
codec on I2C2 to SAI2 with the module's audio configuration.

Signed-off-by: Stefano Radaelli <stefano.r@xxxxxxxxxxxxx>
---
v4->v5:
- Reuse imx6ul-var-som-audio.dtsi for SAI2 and its pinctrl, keeping
codec-specific clock and routing settings in the codec files.
- Add the WM8904 include to the four existing Concerto DTS files in
this patch instead of waiting for a later conversion patch.

v1->v2:
- Share the WM8904 description with a DART-specific microphone
routing wrapper, and consolidate the identical WM8731 files.

.../imx/imx6ul-imx6ull-var-dart-wm8904.dtsi | 17 +++++
.../nxp/imx/imx6ul-imx6ull-var-wm8731.dtsi | 50 ++++++++++++++
.../nxp/imx/imx6ul-imx6ull-var-wm8904.dtsi | 68 +++++++++++++++++++
.../nxp/imx/imx6ul-var-som-concerto-full.dts | 2 +-
.../dts/nxp/imx/imx6ul-var-som-concerto.dts | 2 +-
.../nxp/imx/imx6ull-var-som-concerto-full.dts | 2 +-
.../dts/nxp/imx/imx6ull-var-som-concerto.dts | 2 +-
7 files changed, 139 insertions(+), 4 deletions(-)
create mode 100644 arch/arm/boot/dts/nxp/imx/imx6ul-imx6ull-var-dart-wm8904.dtsi
create mode 100644 arch/arm/boot/dts/nxp/imx/imx6ul-imx6ull-var-wm8731.dtsi
create mode 100644 arch/arm/boot/dts/nxp/imx/imx6ul-imx6ull-var-wm8904.dtsi

diff --git a/arch/arm/boot/dts/nxp/imx/imx6ul-imx6ull-var-dart-wm8904.dtsi b/arch/arm/boot/dts/nxp/imx/imx6ul-imx6ull-var-dart-wm8904.dtsi
new file mode 100644
index 000000000000..236022f3da10
--- /dev/null
+++ b/arch/arm/boot/dts/nxp/imx/imx6ul-imx6ull-var-dart-wm8904.dtsi
@@ -0,0 +1,17 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2026 Variscite Ltd. - https://www.variscite.com
+ */
+
+#include "imx6ul-imx6ull-var-wm8904.dtsi"
+
+&sound_wm8904 {
+ simple-audio-card,routing =
+ "Headphone Jack", "HPOUTL",
+ "Headphone Jack", "HPOUTR",
+ "IN1L", "Line In Jack",
+ "IN1R", "Line In Jack",
+ "IN2L", "Microphone Jack",
+ "IN2R", "Microphone Jack",
+ "Microphone Jack", "MICBIAS";
+};
diff --git a/arch/arm/boot/dts/nxp/imx/imx6ul-imx6ull-var-wm8731.dtsi b/arch/arm/boot/dts/nxp/imx/imx6ul-imx6ull-var-wm8731.dtsi
new file mode 100644
index 000000000000..ed9af0a39714
--- /dev/null
+++ b/arch/arm/boot/dts/nxp/imx/imx6ul-imx6ull-var-wm8731.dtsi
@@ -0,0 +1,50 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2026 Variscite Ltd. - https://www.variscite.com
+ */
+
+#include "imx6ul-var-som-audio.dtsi"
+
+/ {
+ sound {
+ compatible = "simple-audio-card";
+ simple-audio-card,bitclock-master = <&sound_master>;
+ simple-audio-card,format = "i2s";
+ simple-audio-card,frame-master = <&sound_master>;
+ simple-audio-card,name = "wm8731audio";
+ simple-audio-card,routing =
+ "Headphone Jack", "RHPOUT",
+ "Headphone Jack", "LHPOUT",
+ "LLINEIN", "Line Jack",
+ "RLINEIN", "Line Jack",
+ "MICIN", "Mic Bias",
+ "Mic Bias", "Mic Jack";
+ simple-audio-card,widgets =
+ "Headphone", "Headphone Jack",
+ "Line", "Line Jack",
+ "Microphone", "Mic Jack";
+
+ sound_master: simple-audio-card,cpu {
+ sound-dai = <&sai2>;
+ };
+
+ simple-audio-card,codec {
+ sound-dai = <&codec>;
+ system-clock-frequency = <12288000>;
+ };
+ };
+};
+
+&i2c2 {
+ codec: audio-codec@1a {
+ compatible = "wlf,wm8731";
+ reg = <0x1a>;
+ #sound-dai-cells = <0>;
+ clocks = <&clks IMX6UL_CLK_SAI2>;
+ clock-names = "mclk";
+ AVDD-supply = <&reg_3p3v>;
+ DBVDD-supply = <&reg_3p3v>;
+ DCVDD-supply = <&reg_3p3v>;
+ HPVDD-supply = <&reg_3p3v>;
+ };
+};
diff --git a/arch/arm/boot/dts/nxp/imx/imx6ul-imx6ull-var-wm8904.dtsi b/arch/arm/boot/dts/nxp/imx/imx6ul-imx6ull-var-wm8904.dtsi
new file mode 100644
index 000000000000..c95dbf3824af
--- /dev/null
+++ b/arch/arm/boot/dts/nxp/imx/imx6ul-imx6ull-var-wm8904.dtsi
@@ -0,0 +1,68 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2026 Variscite Ltd. - https://www.variscite.com
+ */
+
+#include "imx6ul-var-som-audio.dtsi"
+
+/ {
+ sound_wm8904: sound {
+ compatible = "simple-audio-card";
+ simple-audio-card,bitclock-master = <&sound_master>;
+ simple-audio-card,format = "i2s";
+ simple-audio-card,frame-master = <&sound_master>;
+ simple-audio-card,name = "wm8904audio";
+ simple-audio-card,routing =
+ "Headphone Jack", "HPOUTL",
+ "Headphone Jack", "HPOUTR",
+ "IN1L", "Line In Jack",
+ "IN1R", "Line In Jack";
+ simple-audio-card,widgets =
+ "Microphone", "Microphone Jack",
+ "Headphone", "Headphone Jack",
+ "Line", "Line In Jack";
+ simple-audio-card,mclk-fs = <256>;
+
+ simple-audio-card,cpu {
+ sound-dai = <&sai2>;
+ };
+
+ sound_master: simple-audio-card,codec {
+ sound-dai = <&codec>;
+ };
+ };
+};
+
+&i2c2 {
+ codec: audio-codec@1a {
+ compatible = "wlf,wm8904";
+ reg = <0x1a>;
+ #sound-dai-cells = <0>;
+ clocks = <&clks IMX6UL_CLK_SAI2>;
+ clock-names = "mclk";
+ AVDD-supply = <&reg_3p3v>;
+ CPVDD-supply = <&reg_3p3v>;
+ DBVDD-supply = <&reg_3p3v>;
+ DCVDD-supply = <&reg_3p3v>;
+ MICVDD-supply = <&reg_3p3v>;
+ wlf,drc-cfg-names = "default", "peaklimiter", "tradition",
+ "soft", "music";
+ /*
+ * Config registers per name, respectively:
+ * KNEE_IP = 0, KNEE_OP = 0, HI_COMP = 1, LO_COMP = 1
+ * KNEE_IP = -24, KNEE_OP = -6, HI_COMP = 1/4, LO_COMP = 1
+ * KNEE_IP = -42, KNEE_OP = -3, HI_COMP = 0, LO_COMP = 1
+ * KNEE_IP = -45, KNEE_OP = -9, HI_COMP = 1/8, LO_COMP = 1
+ * KNEE_IP = -30, KNEE_OP = -10.5, HI_COMP = 1/4, LO_COMP = 1
+ */
+ wlf,drc-cfg-regs = /bits/ 16 <0x01af 0x3248 0x0000 0x0000>,
+ /bits/ 16 <0x04af 0x324b 0x0010 0x0408>,
+ /bits/ 16 <0x04af 0x324b 0x0028 0x0704>,
+ /bits/ 16 <0x04af 0x324b 0x0018 0x078c>,
+ /bits/ 16 <0x04af 0x324b 0x0010 0x050e>;
+ };
+};
+
+&sai2 {
+ assigned-clock-rates = <0>, <11565177>;
+};
diff --git a/arch/arm/boot/dts/nxp/imx/imx6ul-var-som-concerto-full.dts b/arch/arm/boot/dts/nxp/imx/imx6ul-var-som-concerto-full.dts
index 725f34d6b7ee..66c9deaea083 100644
--- a/arch/arm/boot/dts/nxp/imx/imx6ul-var-som-concerto-full.dts
+++ b/arch/arm/boot/dts/nxp/imx/imx6ul-var-som-concerto-full.dts
@@ -13,7 +13,7 @@
#include "imx6ul-var-som-wifi.dtsi"
#include "imx6ul-var-som-enet2.dtsi"
#include "imx6ul-var-som-enet1.dtsi"
-#include "imx6ul-var-som-audio.dtsi"
+#include "imx6ul-imx6ull-var-wm8904.dtsi"
#include "imx6ul-var-som-lvds-panel.dtsi"

/ {
diff --git a/arch/arm/boot/dts/nxp/imx/imx6ul-var-som-concerto.dts b/arch/arm/boot/dts/nxp/imx/imx6ul-var-som-concerto.dts
index c249e15772b8..4905abf5aa08 100644
--- a/arch/arm/boot/dts/nxp/imx/imx6ul-var-som-concerto.dts
+++ b/arch/arm/boot/dts/nxp/imx/imx6ul-var-som-concerto.dts
@@ -13,7 +13,7 @@
#include "imx6ul-var-som-concerto-common.dtsi"
#include "imx6ul-var-som-sd.dtsi"
#include "imx6ul-var-som-enet2.dtsi"
-#include "imx6ul-var-som-audio.dtsi"
+#include "imx6ul-imx6ull-var-wm8904.dtsi"
#include "imx6ul-var-som-lvds-panel.dtsi"

/ {
diff --git a/arch/arm/boot/dts/nxp/imx/imx6ull-var-som-concerto-full.dts b/arch/arm/boot/dts/nxp/imx/imx6ull-var-som-concerto-full.dts
index 1b7c1a3383ee..880b72833091 100644
--- a/arch/arm/boot/dts/nxp/imx/imx6ull-var-som-concerto-full.dts
+++ b/arch/arm/boot/dts/nxp/imx/imx6ull-var-som-concerto-full.dts
@@ -13,7 +13,7 @@
#include "imx6ul-var-som-wifi.dtsi"
#include "imx6ul-var-som-enet2.dtsi"
#include "imx6ul-var-som-enet1.dtsi"
-#include "imx6ul-var-som-audio.dtsi"
+#include "imx6ul-imx6ull-var-wm8904.dtsi"
#include "imx6ul-var-som-lvds-panel.dtsi"

/ {
diff --git a/arch/arm/boot/dts/nxp/imx/imx6ull-var-som-concerto.dts b/arch/arm/boot/dts/nxp/imx/imx6ull-var-som-concerto.dts
index 9c9d16eb1a11..c481839a98a5 100644
--- a/arch/arm/boot/dts/nxp/imx/imx6ull-var-som-concerto.dts
+++ b/arch/arm/boot/dts/nxp/imx/imx6ull-var-som-concerto.dts
@@ -12,7 +12,7 @@
#include "imx6ul-var-som-concerto-common.dtsi"
#include "imx6ul-var-som-sd.dtsi"
#include "imx6ul-var-som-enet2.dtsi"
-#include "imx6ul-var-som-audio.dtsi"
+#include "imx6ul-imx6ull-var-wm8904.dtsi"
#include "imx6ul-var-som-lvds-panel.dtsi"

/ {
--
2.47.3